Symbols

[metallibeast]

What's up

I realize that under each article juz below the photo, there are some symbols, like the PG article there are 3 symbols, all about chords have 4...

What does the symbols represent?

-Beast

[szulc]

The Qurter note symbol means it contains musical staff notation.
The speaker symbol means it contains sound files.
The grid Symbol means it contains Tab.
The G symbol means it is guitar oriented.